E90 M3 S65 engine connecting rod bearing replacement

We get randomly the inquiries to update or replace the E90 M3 S65 engine connecting rod bearings. What is the issue at hand, clients ask?

Please keep in mind this is one of the best high reving normally aspirated V8 engines ever built, one of my personal all time favorite. We recommend to disect the oil filter after every oil change just like every experienced Porsche technician used to or still does on the early flat six water cooled Porsche engines, looking for small metallic pieces is the key in here.

The S65 engine is a purpose built race prepped engine with a rather high rpm which will take its toll on the top half of the relatively skinny connecting rod bearings over time. This engine in various iterations were used by BMW for 12 years as their motor sport engine of choice for all of their race cars on their factory teams.

We recommend to use only the best 10/60 fully synthetic motor oils likeLiqui Moly and supplement it it with the Lm2009 Mos2 additive which is a super fine almost molecular fine graphite substance potentially can help the bottom end bearings to be more resilient over long term.

Here are some pictures to see how the removed bearings look alike if removed, replaced in time.

This particular S65 had a hundred fifty thousand kilometers of spirited driving until this point. Naturally timely oil changes will also help in the long run, it’s rather simply just standard common sense.

I also included a disected oil filter from the same engine. Naturally a pair of sharp eyes are an absolute must to catch this issue at hand and address it in a timely manner.